Significance Nearly all eukaryotic physiological events are regulated by protein kinases. Aberrations in functions of kinases are linked to numerous diseases. Significant progress has been made in dissecting the role of many kinases. However, understanding how specific kinases orchestrate complex signaling events remains challenging. Here we present a method to control the timing and the duration of kinase activity. This system provides the ability to mimic physiologically relevant transient activation of a kinase. We demonstrate the specificity and efficiency of this method by regulating tyrosine kinase (c-Src) and serine/threonine kinase (p38α). By using this approach, we identify morphological changes induced by transient activation of Src and demonstrate the role of sequential Src-PI3K and Src-Rac1 signaling in regulation of cell morphology.